Approximately one out of every five posts to Instagram is in square format, according to the Facebook-owned company.

"We know that it hasn't been easy to share this type of content on Instagram - friends get cut out of group shots, the subject of your video feels cramped and you can't capture the Golden Gate Bridge from end to end," Instagram said of being limited to square imagery.

"We're especially excited about what this update means for video on Instagram, which in widescreen can be more cinematic than ever."

Facebook acquired the fast-growing Instagram in 2012 for US$1 billion.